KD spoke about his free agency decision on HOT 97 in NYC Tuesday morning ... saying he was ready to move on from dominating with Golden State to take on a different challenge with a younger team.

“Basketball is the most important thing for me," Durant said. "Kyrie [Irving], DeAndre Jordan, the young players they got was key."

"Playin' with Golden State, playing with a older group I thought it was time for me to impose my will on a younger team.”

This is the part where Knicks fans might wanna look away, 'cause it's about to get ugly.

KD was asked why he went with BK over the NYK ... and he didn't mince his words.

“It's hard to get the best players to play [for the Knicks]. It's hard," KD says.

"I think a lot of fans look at the Knicks as a brand and expect these younger players who, in their lifetime, don’t remember the Knicks being good."

"I saw the Knicks in the Finals, but the kids coming up after me didn’t see that. So, that whole brand of the Knicks, to them, is not as cool to them as, say, a Golden State Warriors or even the Lakers or the Nets now. The cool thing right now is not the Knicks.”

KD says he did, in fact, consider playing for New York ... but it was a very brief "thought" and he didn't explore it that much ... which hurts, given the rumors that he was destined to be a Knick.

"I thought about it, yeah -- just a thought. But, I didn’t do any deep full analysis on the Knicks. I heard it every day -- media in the Bay Area were talkin' about it every day. Tough to dodge, but can’t control it.”

Naturally, Durant is GETTING IT from NY fans on Twitter over the comment ... but he's sticking by his words.